GB2358152A

GB2358152A - Angle grinder dust extractor hood

Info

Publication number: GB2358152A
Application number: GB0000707A
Authority: GB
Inventors: Kevin Holt
Original assignee: MARCRIST IND Ltd; Marcrist International Ltd
Current assignee: MARCRIST IND Ltd; Marcrist International Ltd
Priority date: 2000-01-14
Filing date: 2000-01-14
Publication date: 2001-07-18
Also published as: GB0000707D0

Abstract

A dust extractor hood for an angle grinder comprises a body portion 1 and a flexible skirt 9 removably attached thereto, the skin 9 surrounding and enclosing the grinding blade. The body portion 1 is attachable to the angle grinder and has a dust extraction outlet 3 therein. The skirt 9 is provided with an opening 15, such as a curved slot, through which the edge of the grinding blade is observable and is attached to the body portion 1 by means of a groove 8 provided in the body portion 1 into which a rim 13 provided on the skirt 9 fits. The hood is attached to the angle grinder by means of a split collar 5 on the body portion 1 and a strap or clamp 7. A slot 16 in the body portion 1 provides access to the back up nut on the angle grinder.

Description

2358152

DUST EXTRACTOR HOOD FOR ANGLE GRINDER Field of the Invention

This invention relates to a dust extractor hood for an angle grinder. and to an angle grinder incorporating such a hood.

Background to the Invention

Where angle grinders are used for surface treatment, i.e. with the face of the grinding disc applied to the surface to be treated, it is usual to fit a hood which surrounds the remainder of the disc. The hood serves to protect the operator from accidentally coming into contact with the spinning disc, but principally to extract the dust generated in the grinding process when treating concrete or stone, for example. To this end, the hood will typically be provided with an outlet which can be connected, via a flexible hose, to dust extraction means, for example a vacuum device.

The hood, or at least that part of it which contacts the surface being treated is preferably made of a flexible material, to permit the hood to maintain a dust seal with is the surface while allowing the spinning grinder disc to grind the surface to the desired degree.

A difficulty in the use of an angle grinder fitted with such a hood is that it is not possible to see precisely where the edge of the disc is, thereby making accurate control; of the grinding operation impossible. In addition, there is a risk that the suction applied to the hood to extract dust will cause the flexible hood to adhere to the surface, thereby impeding free movement.

Surnmary of the Invention According to the invention, there is provided a dust extractor hood for an angle grinder, comprising a body portion attachable to the angle grinder and having a dust extraction outlet therein, and a flexible skirt removably attachable to the body portion in such a manner as to surround and enclose the angle grinder blade, in use, wherein the skirt has a greater diameter than the body portion so as to provide a surface extending between the body and the outer circumference thereof, characterised in that the skirt is provided with an opening through said surface through which opening the edge of the angle grinder blade may be observed.

Preferably, the body portion is provided with a circumferential outwardlyfacing groove and the skirt is provided with an inwardly-directed rim which can fit into the groove.

The body portion may be provided with a slot providing access to the backnut 5 on the angle grinder and providing an additional air inlet.

The dust extraction outlet is preferably provided with a hose connector, so that a vacuum dust extraction means can be attached to the device in conventional manner.

The body portion and the skirt may each be moulded in a resilient plastics material, the skirt being made resiliently deformable to facilitate fitting on to the body por- tion and to enable the edge of the skirt to conform with the surface, thereby providing a dust seal with the surface being treated by the angle grinder to prevent escape of dust around the skirt.

The skirt is preferably mounted in such a manner as to permit it to be rotated about the body portion, thereby permitting the opening to be located over any point on the circumference of the grinding disc, so that positioning of the disc can be monitored when working laterally, for example.

The body portion is suitably provided with a split collar which may be fitted on to the body of the angle grinder, an external strap or clamp being used to secure the body portion in position. Inserts may be interposed between the split collar and the body of the angle grinder to accommodate different sized grinder bodies.

The dust extractor hood of the invention is simple to fit and convenient in use, permitting accurate placement of the angle grinder disc without the risk of the vacuum dust extraction equipment causing clamping of the hood on to the surface being treated. Effective removal of dust is achieved.

Brief Description of the Drawings

In the drawings, which illustrate an exemplary embodiment of the invention:

Figure 1 is an exploded side elevation of the hood; and Figure 2 is a top plan view.

Detailed Description of the Illustrated Embodiment

The hood comprises a body portion 1, which is suitably moulded from a ther moplasbcs material such as polypropylene, and has a generally frustoconical section 2 from which extends a dust extraction outlet 3 having a hose connector 4 at the end thereof permitting the push-fit of a hose leading to a vacuum dust extraction device of conventional form (not shown). A split collar 5 surmounts the frusto- conical section 2 to fit on to the body of an angle grinder (not shown), a split-ring insert 6 being used to accommodate any variation between the internal diameter of the collar 5 and the ex ternal diameter of the corresponding part of the angle grinder body. A screw adjustable clip 7 is then used to clamp the collar on to the angle grinder body.

The frusto-conical section 2 of the body has at its lower end a circumferential moulding 8 which provides an outward ly-faci ng groove into which a separate skirt 9 can be fitted. The skirt 9 is moulded in a resilient plastics material, for example polyure thane, and has an open face 10 at which the angle grinder disc contacts the surface to be treated, in use, a cylindrical wall 11 surrounding the periphery of the disc, and an annular end face wall 12 whose inner edge 13 fits into the groove in the moulding 8.

The skirt 9 has moulded into the cylindrical wall 11 adjacent to the open face 10 a rein forcing wire 14 to strengthen the wall 11, although this wire may be omitted. An opening 15 is moulded in the annular end face wall 12. This takes the form of a curved slot serving to permit a section of the rim of the grinder disc to be observed, in use.

This enables accurate machining of the surface by the disc. In addition, the opening 15 admits air to the hood, ensuring that a vacuum effect does not clamp the hood to the work surface, and ensuring that there is an adequate flow of air to carry away the dust generated by the grinding process.

An additional slot 16 may be provided in the frusto-conical section 2 of the body portion to admit a spanner or wrench to engage the back-nut on the angle grinder shaft to facilitate fitting and removal of the disc without the need to remove the hood first.

The slot 16 also admits additional air to assist in removal of dust.

Claims

1 A dust extractor hood for an angle grinder, comprising a body portion attachable to the angle grinder and having a dust extraction outlet therein, and a flexible skirt removably attachable to the body portion in such a manner as to surround arid enclose the angle grinder blade, in use, wherein the skirt has a greater diameter than the body portion so as to provide a surface extending between the body and the outer circumference thereof, characterised in that the skirt is provided with an opening through said surface through which opening the edge of the angle grinder blade may be observed.

2. A dust extractor hood according to Claim 1, wherein the body portion is provided with a circumferential outward ly-faci rig groove and the skirt is provided with an inwardly-directed rim which can fit into the groove.

3. A dust extractor hood according to Claim 1 or 2, wherein the body por tion is provided with a slot providing access to the back-nut on the angle grinder arid providing an additional air inlet.

4. A dust extractor hood according to Claim 1, 2 or 3, wherein the dust extraction outlet is provided with a hose connector, so that a vacuum dust extraction means can be attached to the device in conventional manner.

5. A dust extractor hood according to any preceding claim, wherein the body portion and the skirt are each moulded in a resilient plastics material.

6. A dust extractor hood according to Claim 5, wherein the skirt is resil.

iently deformable.

7. A dust extractor hood according to any preceding claim, wherein the skirt is mounted in such a manner as to permit it to be rotated about the body portion.

8. A dust extractor hood according to any preceding claim, wherein the body portion is provided with a split collar which may be fitted on to the body of the angle grinder, an external strap or clamp being used to secure the body portion in posi tion.

9. A dust extractor hood according to Claim 8, comprising an insert to be interposed between the split collar and the body of the angle grinder.

-S-

10. A dust extractor hood for an angle grinder, substantially as described with reference to, or as shown in, the drawings.